If you want to create new levels, click on the New Level… button. You can…
Vectorworks Tip #257 – Creating a Line Type
Beginner Tip – Use the Resource Browser to create a new Line Type. Use World Units for line types that should be based on real world sizes. Keep the graphics short and simple. If you make the main part of the line type too long, it will not be able to follow curves, or go around corners.